University of Puerto Rico, Rio Piedras Campus MARC Program is requesting funding to continue to provide its thirty four (34) undergraduate students with excellent opportunities to carry out research and to participate in program activities aimed at their professional development. The first aim of this application is to increas the number of highly talented Biology and Chemistry undergraduates that will enter the arena of competitive biomedical research. To this end, each trainee will participate in mentored, hypothesis-driven research project, and will be provided with the necessary skills and tools. This will allow trainees to become highly productive students in any doctoral program in the country and to complete their studies in a manner that leads them to pursue postdoctoral experiences. The MARC Program will continue to organize frequent recruitment seminars, provide technical and professional workshops, as well as special courses directed toward strengthening the research capabilities and communication skills of all its students. It will assure that they attend seminars and take courses that create the knowledge base for their fields. It will also engender an atmosphere that assures that trainees become a cohesive group whose members not only assist each other, but promote doctoral research studies among their peers. In this respect it will seek to assure that 90 percent of its trainees pursue doctoral studies and do so successfully in outstanding research programs. The second aim of this application involves activities that have already shown to have an impact on the numbers of UPR-Rio Piedras Biology and Chemistry majors who are capable of pursuing research careers. These include activities for incoming students that incorporate a Summer Math Immersion and a pre-Chemistry workshop that are designed to improve the academic performance of first-year students. These are followed by a first-year mentoring program that has been found to improve outcomes well beyond their first year. These activities will continue to assure an increased pool of science honor students.